The United States should change its role in the Middle East peace process allowing for more direct talks between Israel and the Palestinians, Israel's chief negotiator Tzipi Livni has said.

The US-brokered peace talks veered toward collapse this week, prompting a warning from Secretary of State John Kerry on Friday, that Washington was evaluating whether it was worth continuing its role in the negotiations.

"Part of what happened in the past few months was more negotiations between us and the United States and less with the Palestinians," Livni told Channel Two's Meet the Press on Saturday.

"I believe we need to move to more meetings, more direct negotiations, more than we have had so far, and I think the Americans know this," Livni said. "American involvement - yes, but as facilitators of bilateral negotiations."

The talks were catapulted into crisis when Israel refused to act on a previously agreed release of Palestinian prisoners unless it had assurances the Palestinians would continue negotiations beyond an initial end-April deadline.

'Unhelpful, unilateral actions'

Kerry flew to Jerusalem on Monday to put the talks back on track but an emerging deal to ensure negotiations go on unravelled after a surprise move by the Palestinians to sign 15 international conventions, mainly through the United Nations, that could give them greater leverage against Israel.

The White House said it was disappointed with both sides for taking "unhelpful, unilateral actions," and signalling his patience with both sides was running out, Kerry said on Friday there was a limit to US efforts if the parties themselves were unwilling to move forward.

Palestinian and Israeli officials said on Saturday that US envoy Martin Indyk was due to meet Livni and Chief Palestinian negotiator Saeb Erekat on Sunday to try and save the talks.

"We will have to struggle to see how we fix it, how we make progress and what we must do to move forward. It is not simple, it is very complicated. It is a real crisis," Livni said.

Talks resumed under Kerry's intensive brokerage in July after a three-year stalemate. Israeli and Palestinian negotiators met regularly for direct talks, but the US stepped up its involvement in the past few months.

The talks have struggled from the start, stalling over Palestinian opposition to Israel's demand that it be recognised as a Jewish state, and over Israeli settlements, internationally deemed illegal, in the occupied West Bank and East Jerusalem.

Palestinians want a state in the West Bank, East Jerusalem - and the Gaza Strip, lands captured by Israel in the 1967 war.